Valve for effecting automatic double inking of the printing plate in a vertical press



Jan. 30, 1962 J. A. ETHIER ,7

VALVE FOR EFFECTING AUTOMATIC DOUBLE INKING OF THE PRINTING PLATE IN AVERTICAL PRESS Filed Feb. 2, 1961 c lind y 35 valve A f d vo/ve 5transfer Vfi C J-1 (y/maelvalve 2 sheaf on c I/nder valve 2 no sheet oncylinder valve open valve closed 5 IN l/ENTOR Joseph Ade/mar E TH/E'R 4BYWWW PATENT AGENT to be printed have relatively large dimensions.

cases, in order to obtain a better printing quality, it is usual toeffect a double'inking of the printing plate. 'A I sheet to be printedis fed to the press only at each two cycles of the machine, that isafter two runs of the inking rollers over the printing plate.

United States PatentO T 3,018,726 VALVE FOR EFFECTING AUTOMATIC DOUBLEINKING OF THE PRINTING PLATE IN A VER- TICAL PRESS Joseph AdelmarEtbier, 6513 De Normanville St., Montreal, Quebec, Canada Filed Feb. 2,1961, Ser. No. 86,700 Claims. (Cl. 101-280) The present inventionrelates to printing press and more particularly to an attachment whichautomatically produces the double inking of the printing plate in avertical printing press.

In the printing art it is usual to print a sheet after a single back andforth inking run of the inking rollers on the printing plate. However incertain cases the quality of the'print is poor mostly when glossy and/orlight colored inks are employed or again when the areas In these 5Several types of printing presses are already equipped with a doubleinking mechanism but presses having a vertical plate and moreparticularly the press known 'under the name Miehle Verticalmanufactured by -M1ehle Printing Press'and Manufacturing Company ofChicago,'Illinois, U.S.A.,, are not provided with such a system and inorder to effect the double inking it is necessary to operate a knob byhand which controls a valve for cutting off the vacuum to the feeder orseparator shoes which transport blank sheets from the feeder table tothe transfer table. This operation must be repeated for each printing ofa sheet and as it is not automatic it requires the constant attention ofthe operator.

The main object of the present invention resides therefore 1n theprovision of a printing press with a vertical plate of the type of theMiehle Vertical printing press and provided with a mechanism forautomatically effectmg double inking.

Another important object of the present invention resides in theprovision of a mechanism of the character described which is very simplein construction and which perfectly synchronizes the necessaryoperations for effect mg double inking in conjunction with the operatingcycle of the press.

Stillanother important object of the present invention resides in theprovision of a valve for effecting double inking which is connected tothe vacuum system of the machine and which functions in dependence withthe ent invention will become more apparent during the followingdisclosure, and by referring to the drawings, in which:

FIGURE 1 is a schematic side elevation of a vertical ,plate printingpress provided with the double inking attachment in accordance with theinvention;

FIGURE 2 is a longitudinal section of the valve for effecting the doubleinking;

FIGURES 3 and 4 are schematic views showing dif- L ferent stages ofoperation for effecting the double inking;

and

3,013,726 Patented Jan. 30, 1962 FIGURE 5 is a schema indicating therelation between the impression cylinder movement and the opening andclosing of the valves of the vacuum circuit.

In the drawings the same reference characters indicated the sameelements throughout.

The Miehle Vertical printing press comprises a bed or frame forvertically mounting a printing plate 1, an impression cylinder 2, atransfer table 3 secured to the frame of the cylinder 2 and a feedertable 4. The plate 1 and impression cylinder 2 are guided in a verticalup and down movement in synchronism but in opposite directions by meansof the racks 5 and 6 respectively secured to the bed of the plate 1 andto the frame of the cylinder 2, said racks meshing with a common pinion7. Inking rollers 8 are also mounted for vertical up and down movementin order to ink the printing plate 1.

In order to transfer a sheet F to be printed one at a time andsuccessively between the different elements of the press, a system isprovided to produce vacuum. This system comprises a vacuum pump 9provided with three valves A, B, C, actuated by cams for opening andclosing these valves in synchronism with the operation of the machine.

The first valve A is connected in series with the tubing 10 whichproduces suction in the separator shoes 11, which serve to separate thetop sheet F from the stack of sheets disposed on the feeder table 4 andtransfer this sheet F onto the transfer table 3. The separator shoes 11are mounted on a transfer bar itself secured to the outer end ofpivotable arms (not shown in the drawings) and v of conventionalconstruction.

The second valve B of the pump 9 is connected in series in the tubing 12which communicate with holes 13 made in a transverse row in the transfertable 3 and which serve to suck and retain a sheet F on the transfertable 3.

The third valve C of the vacuum pump 9 is connected in series in thetubing 14 which communicates with a series of holes 15 made in atransverse row at the periphery of the impression cylinder 2. The holes15 are also in communication with a tubing 16 connected to a diaphragmvalve 17 disposed within the impression cylinder 2 and serving toactuate a clutching mechanism 18. When a sheet F to be printed isretained on the impression cylinder 2 by means of the suction producedthrough holes 15 there is an increase of vacuum in the diaphragm valve17 which produces the clutching of the cylinder and rotation of thelatter for printing the sheet by the printing plate 1 when the cylindermoves upwardly and the printing plate moves downwardly through the racksS and 6 and pinion 7.

The printing press operates in the following conventional manner. Duringthe upward stroke of the impression cylinder 2 and of the transfer table3 to finally reach transfer table 3 in the topmost position of thecylinder 2.

The valve A closes and the sheet is released by the shoes 11 onto thetable 3 and is retained thereon by suction exerted by holes 13, valve Bhaving been previously opened as shown in FIGURE 5.

The table 3 and impression cylinder 2 then move downwardly but thecylinder does not rotate because valve C is closed and during this timethe plate 1 moves upwardly and is inked by the inking rollers 8, whichagain ink the plate during the downward movement of the latter. When thecylinder reaches its lowermost position, the valve B closes releasingthe sheet F on the transfer table 3 and said sheet is transferred fromthe table 3 to the periphery of cylinder 2 by means of grippers 19 andis positioned on the cylinder in such a way that the marginal portion ofthe sheet will close or block the holes opening at the surface of thecylinder 2.

Valve C opens for a short time and the higher vacuum existing in tubing14, holes 15 being blocked, actuate the diaphragm valve 17 which causesclutching of cylinder 2 whereby during subsequent upward movement of thecylinder the latter will rotate in the direction of arrow 20 (see FIGURE3), during which time plate 1 moves downwardly to print the sheet on thecylinder 2.

If the holes 15 would have remained opened in the absence of a sheet onthe cylinder, the lower degree of vacuum in tubing 14 and 16 would havebeen insufficient to cause clutching and rotary impression movement ofthe cylinder 2. When the cylinder 2 has reached its top most position,the sheet on the cylinder is released, rotation of the cylinder isstopped and the delivery grippers 21 transport the printed sheet ondelivery table (not shown).

Therefore during the upward stroke of the cylinder 2, the separatorhaving the separator shoes 11 transfers a blank sheet from the feedertable 4 to the transfer table 3 and the cylinder meanwhile printsanother sheet mounted on said cylinder. When the cylinder and thetransfer table 3 are in their topmost position, there is transfer of aprinted sheet from the cylinder to the delivery table and each time thecylinder and its transfer table 3 are in their lowermost position thereis a transfer of a blank sheet from said transfer table 3 to thecylinder 2. Thus a printing step occurs each time the cylinder movesupwardly and inking of the printing plate at each cycle of the cylinder.Therefore, there is a single inking and the press does not have anyautomatic means for effecting double inking.

In accordance with the present invention, the means for effecting doubleinking comprises a valve 25 more particularly illustrated in FIGURE 2.The body of this valve defines a cylindrical chamber 26 closed at oneend by a perforated removable cover 27 maintained in position by a lockwasher 27'. A piston 28 is reciprocable Within the chamber 26 and isprovided with a piston rod 29 passing through the hole of cover 27 andhaving an externally threaded end for receiving a nut 30 and a wingnut31. A coil spring 32 surrounds the piston rod 29 and abuts at one endagainst washer 27 and at the other end against the nut 30. Spring 32normally resiliently retains the piston 28 in upper limit rest positionin which it abuts against cover 27. Piston 28 is provided at itsperiphery with an annular groove 33 completely surrounding the pistonand having a circular rectangular or square cross section. The groove 33is disposed opposite ports 34 and 35 opening within the valve chamber 26and disposed at right angles to each other so that groove 33 establishescommunication between said two ports in the rest position of the piston28. The port 34 is at the end of a bore in the valve body 25 which isconnected to tubing 10 while port 35 opens at the exterior of the valvebody to be connected to the transfer shoes 11.

Valve A of the press establishes communication between the vacuum pump 9and the transfer shoes 11 in the rest position of the piston 28, in thesame manner as if valve 25 was absent. The end of the cylinder 26opposed to cover 27 is provided with an opening 36 in communication witha tube 37 which is connected to tubing 14 already connected to the holes15 of the impression cylinder 2. The force exerted by spring 32 isadjusted by means of the nuts 30 and 31 in such a way that when there isno sheet F on the impression cylinder 2 and that i the holes 15 aretherefore opened to the atmosphere, the vacuum existing in tubing 14 andtube 37 is insufficient for producing the displacement of the piston 28in valve 25 against the action of spring 32. On the other hand,

when there is a sheet F on the impression cylinder and this sheet blocksholes 15, there is an increase in the vacuum in tubing 14 and tube 37and the vacuum is sufiicient to produce displacement of piston 28against action of spring 32 to thereby close the communication betweenthe ports 34 and 35 and stop suction exerted by the transfer shoes 11 onthe topmost sheet F on the stack of sheets on feeder table 4.

The insertion of valve 25 in the vacuum circuit of the press effects thedouble inking in the following manner:

FIGURES 3 and 4 of the drawings illustrate the cylinder 2 and thetransfer table 3 a little above their lowermost position andcorresponding to point 38 in the schema of the upward and downwardmovements of the cylinder illustrated in FIGURE 5. FIGURE 3 illustratesthe cylinder on which there is no sheet F to be printed. The vacuumproduced in tubes 14 and 37 is insufficient for closing valve 25 andtherefore there is vacuum at the transfer shoes 11. Thus during theupward stroke of the cylinder, valve A opens and a sheet F istransferred onto the transfer table 3. This sheet is thereaftertransferred onto the cylinder 2 and during the subsequent upward strokeof said cylinder, this sheet is printed. But as this sheet is on thecylinder, as indicated in FIGURE 4, the vacuum is higher in tubes 14 and37 during opening of valve C because holes 15 of cylinder 2 are blockedby said sheet. Thus valve 25 closes and the transfer shoes 11 areinactive and there is no transfer of the sheet between feeder table 4and transfer table 3. Therefore in the subsequent upward stroke of thecylinder, the latter remains bare and there is no printing taking place.Thus, the transfer shoes 11 are alternately active and inactive at eachupward stroke of the cylinder and therefore a sheet is fed for printingat each two cycles of the press and double inking can be produced, thatis two back and forth runs of the inking rollers on the printing plate1.

If desired, there can be provided means for blocking the piston 28 inits upper limit position, for instance a pin can be inserted in a holemade in the piston rod 29 just above the top of the valve body 25 inorder to prevent downward movement of the piston. This can be effectedto prevent double inking whenever desired.

While a preferred embodiment in accordance with the present inventionhas been illustrated and described it is understood that variousmodification may be resorted to without departing from the spirit andscope of the appended claims.

What I claim is:

1. In a printing press including a vertical printing plate, animpression cylinder cooperating with said printing plate in a verticalup and down movement, a transfer table associated with said cylinder, afeeder table mounted on said press at substantially the level of saidtransfer table in the topmost position of the latter, means fortransferring a blank sheet to be printed from said feeder table to saidtransfer table, means for transferring a blank sheet from said transfertable to said cylinder, a vacuum supply, a first valve and a firsttubing connecting said first named means to said supply, said transfertable having holes at its surface, a second valve and a second tubingconnecting said holes of said transfer table to said vacuum supply, saidcylinder having a series of holes at its periphery, a third valve and athird tubing connecting said cylinder holes to said vacuum supplywhereby a sheet on said cylinder blocks said cylinder holes and producesan increase of vacuum in said third tubing, .the combination with saidpress of a valve mounted in series with said first tubing and comprisingan element movable between a first position and a second positionblocking and opening said first tubing, respectively, by-pass tubingconnecting said third tubing to said valve, said movable element takingits blocking position under an increase of vacuum in said third tubingand in said by-pass tubing, that is when a sheet blocks the holes ofsaid cylinder, and said movable element taking its opening position ofsaid first tubing upon a decrease of vacuum in said third tubing andby-pass tubing, that is when said cylinder holes are opened toatmosphere.

2. In a printing press including a vertical printing plate, animpression cylinder cooperating with said printing plate in a verticalup and down movement, a transfer table associated with said cylinder, afeeder table mounted on said press at substantially the level of saidtransfer table in the topmost position of the latter, means fortransferring a blank sheet to be printed from said feeder table to saidtransfer table, means for transferring a blank sheet from said transfertable to said cylinder, a vacuum supply, a first valve and a firsttubing connecting said first named means to said supply, said transfertable having holes at its surface, a second valve and a second tubingconnecting said holes of said transfer table to said vacuum supply, saidcylinder having a series of holes at its periphery, a third valve and athird tubing connecting said cylinder holes to said vacuum supplywhereby a sheet on said cylinder blocks said cylinder holes and producesan increase of vacuum in said third tubing, the combination with saidpress of a valve mounted in series with said first tubing and comprisingan element movable between a first position and a second positionblocking and opening said first tubing, respectively, by-pass tubingconnecting said third tubing to said valve, said movable element takingits blocking position under an increase of vacuum in said third tubingand in said by-pass tubing, that is when a sheet blocks the holes ofsaid cylinder, and said movable element taking its opening position ofsaid first tubing upon a decrease of vacuum in said third tubing andby-pass tubing, that is when said cylinder holes are opened toatmosphere, said valve comprising a body having a cylindrical chamberand said movable element consisting of a cylindrical piston movablewithin said valve comprising a body having a cylindrical chamber andsaid movable element consisting of a cylindrical piston movable withinsaid chamber and provided with a peripheral annular groove, said firsttubing opening within said chamber by means of ports in register withsaid groove in the opening position of said piston, a spring disposedbetween said piston and said valve body and resiliently maintaining saidpiston in its opening position, said by-pass tubing being connected to aport in said cylindrical chamber opposite an end of said piston wherebyincrease of vacuum produced in said by-pass tubing and in saidcylindrical chamber causes displacement of said piston towards saidby-pass port and causes said piston to take its blocking position.

3. The combination as claimed in claim 2, further including means foradjusting the force exerted by said spring.

4. The combination as claimed in claim 2, wherein said piston has apiston rod protruding from said valve body, said piston rod having athreaded outer end, a nut screwed on said end, said spring surroundingsaid piston rod and abutting against said nut and against said valvebody.

5. The combination as claimed in claim 2, wherein said groove has arectangular cross-section.

References Cited in the file of this patent UNITED STATES PATENTS872,108 Brett Nov. 26, 1907 1,942,490 Quizley J an. 9, 1934 1,956,647McCoy May 1, 1934 1,957,812 Stein May 8, 1934 1,974,544 Rowell Sept. 25,1934

